This application claims priority from Japanese patent application Serial no. 2001-263377 filed Aug. 31, 2001, the contents of which are incorporated by reference herein.
1. Field of the Invention
This invention relates to a control apparatus for automatically changing plate cylinders for use in a rotary press comprising a plurality of printing sections; each printing section having a plate cylinder and ink feeding means for feeding ink to a printing plate surface on the outer peripheral surface of the plate cylinder, independent printing drive means for driving at least a plate cylinder, a first state changing unit for independently changing at least each plate cylinder from the printing state enabling printing to the non-printing state disabling printing, and a second state changing unit for independently changing each ink feeding means from the ink feeding state enabling ink feeding to the ink non-feeding state disabling ink feeding; the plate cylinder that may be in printing operation being automatically changed so that a preceding printing operation can be continuously taken over without stopping the rotary press by a succeeding printing operation where a printing material having in whole or in part different printing contents form those printed in the preceding printing operation is printed.
2. Description of the Related Art
A rotary press comprising a plurality of printing sections so that a preceding printing operation can be continuously taken over without stopping the rotary press by a succeeding printing operation where a printing material having in whole or in part different contents from those printed in the preceding printing operation is printed by changing plate cylinders being used for printing operation has been disclosed in Japanese Published Unexamined Patent Application No. Hei-8 (1996) -207233, for example.
This rotary press comprises a plurality of printing sections; each printing section having at least independent drive means for driving the plate cylinder thereof, and a unit for independently changing over each plate cylinder from a printable state to an unprintable state or vice versa so that plate cylinders used in the preceding printing operation can be changed in part or in whole in the succeeding printing operation where a printing material having in part or in whole different contents from those printed in the preceding printing operation is printed.
In this rotary press, plate cylinder changing and speed adjustment for independently changing over each plate cylinder from a printable state to an unprintable state as necessary are accomplished by a control apparatus when changing over a preceding printing operation to a succeeding printing operation.
In Japanese Published Unexamined Patent Application No. Hei-8 (1996) -207233, no specific details about control using the control apparatus are disclosed. In particular, no specific details about control processing as to how a plate cylinder being changed over is designated when changing plate cylinders to independently change over each plate cylinder from a printable state to an unprintable state as necessary, or as to how the timing of actuating the plate cylinder that has been stopped and left in the unprintable state, increasing the speed thereof to match with the printing operation speed of the rotary press at that point of time is determined, are not disclosed.
In printing operation, the required number of print copies is determined in advance for each printing materials. The number of print copies prior to the changeover of plate cylinders therefore has to be set to the required minimum to minimize, or eliminate, unnecessary printing paper (spoilage). In the rotary press disclosed in Japanese Published Unexamined Patent Application No. Hei-8 (1996) -207233, it is not clear how these requirements can be satisfied.
It is an object of the present invention to provide rotary press control apparatus for use in a rotary press comprising a plurality of printing sections, in which the number of print copies prior to the changeover of plate cylinders can be reduced to the required minimum, making it possible to achieve printing with unnecessary printing paper (spoilage) minimized or eliminated, thus preventing printing cost from increasing due to generation of unnecessary printing paper (spoilage) in a printing operation where a preceding printing process can be continuously changed, without stopping the rotary press, to a succeeding printing operation where a printing material having in part or in whole different contents from those printed in the preceding printing operation is printed.
To achieve these objectives, the present invention provides a control apparatus for automatically changing plate cylinders for use in rotary press which provides a plurality of printing units, wherein each printing unit comprises at least a plate cylinder and an ink feeder to the printing plate surface on the outer periphery of the plate cylinder, a printing drive unit to drive at least a plate cylinder, a first state changing unit to individually change at least each plate cylinder from a printing state enabling printing to a non-printing state disabling printing, a second state changing unit to change each ink feeder from an ink feeding state enabling ink feeding to the printing plate surface to an ink non-feeding state disabling ink feeding, wherein the apparatus comprises; a reference control section performing an input operation of at least an operation instruction for a printing operation, such as start, acceleration/deceleration and stop, outputting a drive reference corresponding to the operation instruction, and selectively outputting a monotonously increasing reference speed that monotonously increases at a predetermined gradient and a monotonously decreasing reference speed that monotonously decreases at a predetermined gradient, aside from the outputting of the drive reference; a drive control section being provided for each printing drive unit for controlling the rotation of the printing drive unit on the basis of a signal from the reference control section; a printing control section setting a required number of print copies for a printing operation, carrying out a first calculation where xe2x80x9c1xe2x80x9d is subtracted from the required number of print copies for the printing operation every time a printing material is detected at a predetermined detecting position and a second calculation where a period of time for a currently stopped printing drive unit to be driven at the monotonously increasing reference speed and reach a printing operation speed at that point of time in the printing operation is calculated, calculating the number of printing materials to be printed when the printing operation at that point of time is continued for the calculated period of time, and subtracting at all times the sum of the calculated number of printing materials and a predetermined constant from the value obtained in the first calculation, outputting a first signal when a value obtained in the second calculation becomes less or equal xe2x80x9c0,xe2x80x9d and outputting a second signal when a value obtained as the calculation result of the first calculation becomes less or equal xe2x80x9c0;xe2x80x9d and an operation control section outputting a state changing signal for operating the first state changing unit to change the state of plate cylinders, and the second state changing unit to change the state of the ink feeder, wherein the drive control section outputs the monotonously increasing reference speed in response to the output of the first signal in a predetermined relationship, and outputs the monotonously decreasing reference speed in response to the output of the second signal in a predetermined relationship, and the operation control section outputs an operation signal for operating the first state changing unit and the second state changing unit in response to the output of the second signal in a predetermined relationship.
Furthermore, the control apparatus according to the present invention may be characterized in that an reference control section designates a printing section to be used in a first printing operation or distinguishes and designates a printing section to be newly used and the printing section that has been designated for the preceding printing operation and is to be continuously used for each of the subsequent printing operations is provided.
Furthermore, the control apparatus according to the present invention may be characterized in that the printing control section is provided in such a manner that the number of effective printing materials upstream of a predetermined detecting position at which printing materials are detected can be set, and that the number of effective printing materials in the upstream can be subtracted from the required number of print copies during the first calculation.
Furthermore, the control apparatus according to the present invention may be characterized in that the reference control section is provided as a master control section, and the drive control section is provided as a slave control section subordinated to the master control section.
The present invention also provides a control method for automatically changing plate cylinders for use in a rotary press providing a plurality of printing units, wherein each printing unit comprises at least a plate cylinder and an ink feeder to the printing plate surface on the outer periphery of the plate cylinder, a printing drive unit to drive at least a plate cylinder, a first state changing unit to individually change at least each plate cylinder from a printing state enabling printing to a non-printing state disabling printing, a second state changing unit to change each ink feeder from an ink feeding state enabling ink feeding to the printing plate surface to an ink non-feeding state disabling ink feeding, the method comprises the steps of performing the input operation of at least an operation instruction for a printing operation, such as start, acceleration/deceleration and stop, outputting a drive reference corresponding to the operation instruction, and selectively outputting a monotonously increasing reference speed that monotonously increases at a predetermined gradient and a monotonously decreasing reference speed that monotonously decreases at a predetermined gradient, aside from the outputting of the drive reference, being provided for each printing drive unit for controlling the rotation of the printing drive unit on the basis of a signal from the reference control section, setting a required number of print copies for a printing operation, carrying out a first calculation where xe2x80x9c1xe2x80x9d is subtracted from the required number of print copies for the printing operation every time a printing material is detected at a predetermined detecting position and a second calculation where a period of time for a currently stopped printing drive unit to be driven at the monotonously increasing reference speed and reach a printing operation speed at that point of time in the printing operation is calculated, calculating the number of printing materials to be printed when the printing operation at that point of time is continued for the calculated period of time, subtracting at all times the sum of the calculated number of printing materials and a predetermined constant from the value obtained in the first calculation, outputting a first signal when a value obtained in the second calculation becomes less or equal xe2x80x9c0,xe2x80x9d and outputting a second signal when a value obtained as the calculation result of the first calculation becomes less or equal xe2x80x9c0;xe2x80x9d and outputting a state changing signal for operating the first state changing unit for changing the state of plate cylinders, and the second state changing unit for changing the state of the ink feeding means feeding ink, wherein the drive control section outputs the monotonously increasing reference speed in response to the output of the first signal in a predetermined relationship, and outputs the monotonously decreasing reference speed in response to the output of the second signal in a predetermined relationship and the operation control section outputs an operation signal for operating the first state changing unit and the second state changing unit in response to the output of the second signal in a predetermined relationship.
In one preferred mode, the present invention starts the control apparatus for automatically controlling plate cylinders according to the present invention prior to a printing operation, enters into the printing control section for memory at least information on printing cylinders being used and individual printing information including the required number of print copies for each of several printing operations scheduled to be continuously operated. The reference control section receives the printing information, and combines the drive control sections for the drive means to be controlled in that printing operation and designates them as a group.
Upon completion of group designation, the printing operation is started. The printing operation is carried out as the drive means are driven via the drive control section on the basis of the drive reference output by the reference control section in accordance with the operation instructions from the input processing section.
As the printing operation is started, a printing material is detected at a predetermined position and subtracted from the required number of print copies in the printing control section. At the printing control section, the drive reference output by the reference control section is input at all times and the printing operation speed at that point of time is recognized. At the same time, when the drive means that has been stopped at that point of time is driven via the drive control section on the basis of the xe2x80x9cmonotonously increasing reference speedxe2x80x9d output by the reference control section, the time required until the drive means reaches the printing operation speed at that point of time is calculated, and the number of printing materials printed when the printing operation at that point of time is continued as long as the calculated time.
Then, the calculated number of printing materials and a predetermined constant (integer), which will be described later, are subtracted from the aforementioned required number of print copies. When the value obtained by subtracting the detected number of printing materials, the calculated number of printing materials and the predetermined constant (integer) from the required number of print copies becomes less or equal xe2x80x9c0,xe2x80x9d the printing control section outputs a first signal. Furthermore, when the value obtained by subtracting only the detected number of printing materials from the required number of print copies becomes less or equal xe2x80x9c0,xe2x80x9d the printing control section outputs a second signal.
Or, the first signal and the second signal mentioned above are output at the point of time when the value obtained by subtracting the number of effective printing materials upstream of a predetermined detecting position at which printing materials are detected, together with them, from the required number of print copies becomes less or equal xe2x80x9c0.xe2x80x9d As the aforementioned predetermined constant (integer), used is a number slightly greater than the number of printing material to be printed at the maximum printing operation speed during the period of time required for the drive means that has been driven from the stopped state at that point of time at the xe2x80x9cmonotonously increasing reference speedxe2x80x9d and reached the printing operation speed at that point of time to be phase-adjusted to match with the phase of the drive reference signal so that the drive means comes to have a phase in which printing operation is possible.
Upon receipt of the first signal, the reference control section outputs a xe2x80x9cmonotonously increasing reference speedxe2x80x9d to the drive control section corresponding to the drive means so as to start the drive means of the printing section that has not been used in the current printing operation and is to be used in the next printing operation, and increase the speed thereof to the printing operation speed at that point of time.
As a result, the drive control section to which the xe2x80x9cmonotonously increasing reference speedxe2x80x9d is input actuates the corresponding drive means in accordance with the xe2x80x9cmonotonously increasing reference speedxe2x80x9d to increase the speed of the drive means. As the xe2x80x9cmonotonously increasing reference speedxe2x80x9d agrees with the reference speed of the xe2x80x9cdrive referencexe2x80x9d output by the drive control section, then the drive control section changes over the output to the drive control section to which the xe2x80x9cmonotonously increasing reference speedxe2x80x9d has been input to the xe2x80x9cdrive referencexe2x80x9d so as to control the rotation of the drive means corresponding to the drive control section on the basis of the xe2x80x9cdrive reference.xe2x80x9d
Not only the drive means but also the printing cylinders, such as the plate cylinders, that have been shifted to the control on the basis of the drive reference output by the reference control section are controlled so as to be operated in a phase enabling printing operation. After the drive means, that is, the aforementioned printing cylinders have been controlled so as to be operated in a phase enabling printing operation, a second signal is output. The second signal is input into the operation control section and the reference control section.
Upon receipt of the second signal, the operation control section actuates the second state changing unit of the printing section that has been used in the current printing operation and is not to be used in the next printing operation so as to change into an ink non-feeding state, and at the same time actuates the second state change unit of the printing section that has not been used in the current printing operation and is to be used in the next printing operation to change into an ink feeding state.
The operation control section then actuates the first state changing unit of the printing section that has not been used in the current printing operation and is to be used in the next printing operation to change into a printing state, and at the same time actuates the first state changing unit of the printing section that has been used in the current printing operation and is not to be used in the next printing operation to change into a non-printing state.
When the first state changing unit of the printing section that has been used in the current printing operation and is not to be used in the next printing operation is changed to a non-printing state, the reference control section outputs a xe2x80x9cmonotonously decreasing reference speedxe2x80x9d to the drive control section corresponding to the drive means of the printing section that has been used in the current printing operation and is not to be used in the next printing operation so as to stop that drive means. The drive control section to which the xe2x80x9cmonotonously decreasing reference speedxe2x80x9d is input decelerates and stops the corresponding drive means in accordance with the xe2x80x9cmonotonously decreasing reference speed.xe2x80x9d